feat: event-log kernel — durable Event sidecar + replay-capable consumer#2
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feat: event-log kernel — durable Event sidecar + replay-capable consumer#2
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Adds a new durable artifact: every session now writes a typed Event log to ~/.reasonix/sessions/<name>.events.jsonl as a sidecar to the existing ChatMessage / transcript files. Foundation for future replay / projection / multi-agent consumers reading kernel events instead of LoopEvent. Architecturally a pure addition: no edits to loop.ts, transcript.ts, EventLog, log-frame, replay, dashboard server, or any existing test. LoopEvent stays as the internal protocol between loop and immediate consumers — events.jsonl is a parallel kernel artifact, not a migration target. - src/core/eventize.ts: pure stateful translator. Holds monotonic event id seq, last-turn tracker (synthesizes model.turn.started), and a callId stack (correlates tool.intent → tool.dispatched → tool.result chains since LoopEvent.tool_start doesn't carry call.id). - src/adapters/event-sink-jsonl.ts: concrete EventSink port impl — append-only JSONL with append/flush/close lifecycle. eventLogPath helper derives the sidecar path from a session name (mirrors src/session.ts:sessionPath). - src/cli/ui/App.tsx: ~30 lines additive — refs for sink + eventizer opened on session mount (skipped for ephemeral sessions), pipe attached inside the existing for-await consumer alongside writeTranscript, sink.close on unmount, session.opened emitted at open time. - tests/eventize.test.ts: 11 unit tests pinning the mapper — turn-start synthesis, delta channel split, tool callId correlation, error detection, warning categorization, control- marker passthrough. 1737 tests pass (was 1726 + 11 new). Zero existing-test edits.
Closes the loop on the v0.14 kernel architecture: the events.jsonl sidecar from the prior commit is now demonstrably reduceable into a useful projection. Synthetic LoopEvents → Eventizer → JsonlEventSink → disk → JsonlEventSource → reducers.replay() → ProjectionSet round- trips correctly, conversation messages reconstructed in order, tool result correlation preserved, replay() deterministic across runs. This is the architecture-value tipping point: events are no longer just write-only artifacts, they're the source of truth a consumer can rebuild state from. Future work — UI re-rendering from a projection, time-travel, multi-agent event trees — has a working foundation. - src/adapters/event-source-jsonl.ts: EventSource port impl. Pure read side: parses jsonl, skips malformed lines silently (best- effort replay over a possibly-truncated live writer). - tests/event-sink-jsonl.test.ts: 5 tests pinning the sink mechanics (append-per-line round-trip, re-open on existing file, parent dir creation, flush no-op, port-shape conformance). - tests/event-replay.test.ts: 5 tests pinning the architecture promise — synthetic LoopEvents reduce to expected projections, error-shaped tool results land with ok=false, replay determinism, missing-file safety, malformed-line tolerance. 1747 tests pass (was 1737 + 10 new). Zero touches to existing production code.
This was referenced Apr 29, 2026
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Summary
Builds the event-log kernel as a new durable artifact alongside the existing LoopEvent stream, NOT as a migration target. Future replay / projection / multi-agent consumers read kernel events from the sidecar; the working LoopEvent path stays untouched.
This is the D approach chosen after evaluating the big-bang LoopEvent removal: instead of ~250 mechanical edits across 29 files (and the regression risk that comes with it), we add 7 new files and a 40-line additive wire-up. Architecture value is tangible immediately (an event log exists and is reducible) without forcing a migration.
f0ca5bc):Eventizertranslator +JsonlEventSink+ App.tsx wire-up. Every session writes typed Events to~/.reasonix/sessions/<name>.events.jsonlas a sidecar.f50de58):JsonlEventSourcereader + round-trip test proving that synthetic LoopEvents → Eventizer → sink → disk → source → reducers → ProjectionSet reconstruct the conversation correctly.Architectural rationale
Reframed the question from "how do we migrate off LoopEvent" to "what's the smallest correctness-preserving change that builds the kernel artifact and lets new consumers exist":
Files
New (7):
src/core/eventize.ts— translator state machinesrc/adapters/event-sink-jsonl.ts—EventSinkport impl (write side)src/adapters/event-source-jsonl.ts—EventSourceport impl (read side)tests/eventize.test.ts— 11 mapper teststests/event-sink-jsonl.test.ts— 5 sink mechanics teststests/event-replay.test.ts— 5 round-trip + projection testsModified (1, additive only):
src/cli/ui/App.tsx— ~40 lines: refs for sink + eventizer, open on session mount, pipe inside the existing for-await consumer alongsidewriteTranscript, close on unmountUntouched:
loop.ts,transcript.ts,replay.ts,EventLog.tsx,log-frame.tsx,LiveRows.tsx, dashboard server, subagent — and every existing test file.Test plan
npm run verify— 1747 tests pass (was 1726 + 21 new)npm run lint— cleannpm run typecheck— cleanreasonix codefor a session, confirm~/.reasonix/sessions/<name>.events.jsonlappears with parseable JSONL — one event per line, monotonic ids, correct turn numbers,model.turn.startedat every turn boundary,tool.intent→tool.dispatched→tool.resultchain with matching callIdsWhat this unlocks (future PRs, not this one)